I thought this was an interesting article about how this novel virus works. It blocks signals that your cells give off that triggers an immune response which is why it's able to spread before showing symptoms. It also has the ability to proof-read and correct new copies that prevents mutations that could cripple the virus.
https://www.scientificamerican.com/interactive/inside-the-coronavirus/?fbclid=IwAR0nBQsZ8K8ARvVjxMYfLHKPgJ6cfI5mFwY-vzvllpSNaO8h5vMYklbrt9U